Heretofore, in a manufacturing process for an organic EL device, in order to seal an organic EL substrate, a sealing substrate is adhered to the organic EL substrate with an adhesive. In this sealing process, a gap agent is mixed with the adhesive for controlling the gap between the sealing substrate and the organic EL substrate so that, even when the sealing substrate is contact bonded thereto, the thickness of an adhesive layer formed of the adhesive is not decreased to less than the diameter of the gap agent to make the thickness of the adhesive layer have a desired predetermined value. Subsequently, when deformed in a predetermined amount by contact bonding of the sealing substrate, the adhesive layer is cured by irradiation with ultraviolet rays or by heating. The conventional method for controlling the gap between the two substrates, as described above, has also been used in a manufacturing process for liquid crystal panels.